const MessageDecorator: ClassDecorator = (target: Function) => {
  target.prototype.message = (content: string): void => {
    console.log(content);
  }
}

@MessageDecorator
class LoginController {
  public login() {
    console.log('登录业务处理');
    // console.log('登录成功消息');
    this.message('恭喜你登陆成功')
  }

}

new LoginController().login()